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    <script>
        var a =10;
        ++a; // ++a = 11   a=11
        var b = ++a + 2; //++ a = ++ 11 = 12  12+2=14
        console.log(b); // 14
        
        var c = 10;
        c++; // c++ = 11
        var d = c++ + 2; // c++ = 11 c= 12 11+2=13
        console.log(d); // 13

        var e =10;
        var f =e++ + ++e; //e++ =10   ++e = 11 
        console.log(f); // 21
    </script>
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